Electrostatic atomizers

Abstract

An electrostatic atomizer includes a body defining an interior space and a discharge orifice communicating with the interior space. An emitting electrode or electron gun is disposed inside the body so as to apply charges to the fluid passing through the interior space. A counter electrode is disposed outside the body. The exposed surfaces on the interior of the body are formed from a dielectric material so that there is no substantial electric field between exposed conductive elements on the inside of the body. This arrangement minimizes soot buildup and plugging of the orifice. The device may include a single element defining numerous orifices and formed by micro-machining techniques such as those used in fabrication of semiconductor devices. Orifice sizes as small as a few micrometers can use successfully to provide controllable atomization at extremely low flow rates.

1 . A method of atomizing a fluid comprising the steps of: 
 (a) passing the fluid through an interior space within a body and out of the interior space through a discharge orifice; and    (b) applying a net charge to the fluid so that the fluid passing out of the discharge orifice will be atomized under the influence of said net charge, said step of applying a net charge being performed without exposing the fluid to an electric field between exposed conductive surfaces within said interior space in excess of 1000 V/mm.    
     
     
         2 . A method as claimed in  claim 1  wherein said step of applying an net charge is performed by maintaining an electric field between a charge injection electrode within said interior space and a counter electrode outside of said interior space and separated therefrom by a dielectric.  
     
     
         3 . A method as claimed in  claim 2  wherein said discharge orifice has a diameter of less than about 100 μm.